Decision takenRobben played both of the Netherlands' UEFA EURO 2008™ qualifiers this week, but returned to the Premiership club to have tests on the injured knee, prompting the decision today to undergo surgery.

'Out for a long time'Chelsea boss José Mourinho said: "Robben will be out for a long time. He played two matches for his country, 90 minutes [against Slovenia] last Wednesday, and the next day he came here and he is injured. He needs surgery and we lose an important player, maybe for the rest of the season." The consolation for Chelsea ahead of their UEFA Champions League quarter-final against Valencia CF on 4 and 10 April is the imminent return of Joe Cole – "Cole is coming back and maybe next week we have him," Mourinho added. Robben has made 21 Premiership appearances this season for second-placed Chelsea, and another seven in Europe.

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